Integral, board-like components of the type described at the outset are known in various forms, for example from DE-38 32 351-A1, according to which a resin with a filler formed at least predominantly of quartz particles has a denser packing of the filler in the regions of the component which are subject to considerable wear and tear during use than on the back of the component.
This is achieved by allowing the filler to settle at least to a certain degree in the case of the casting mass consisting of resin and filler which is filled into the mold, and thus a concentration at the visible side of the component containing the regions subject to wear and tear is achieved.
With this process, components with very good functional properties can be produced, for which reason these components have also found a wide acceptance on the market, in particular in the form of sinks. In particular, the abrasion resistance, the resistance to scratching, the cleanability as well as the granite-like appearance of the visible side resulting from a corresponding selection of the filler number amongst the very good functional properties.
These positive functional properties are also of great value, above all, in the case of board-like materials, such as, for example, working surfaces in the kitchen, washstand tops in the bathroom etc., but it has been found that it is very difficult or even impossible to ensure a good planarity when the components have larger dimensions. In addition, the density of such components is considerably higher than the density which is customarily obtained for chipboard and this results, in the case of working surfaces 20 to 44 mm thick, in components which are very difficult to handle.
When planar components are obtained during production, a bending of the board is observed at the latest during changes in temperature, namely during changes in temperature such as those which often occur during the transportation of such boards in trucks, during which storage (for example overnight in the truck) at temperatures of between -15 and -20.degree. C. very often occurs (for example in Scandinavian countries) while during the day with corresponding sunshine temperatures of up to 80.degree. C. can be reached in the transport vehicle. Short storage times at different temperatures, for example in the range of hours, can already be sufficient to result in a permanent deformation of the board which can no longer be reversed and so the component can no longer be used following transportation.
Alternatively hereto, chipboard is, of course, conceivable as carrier with a thin, filled plastic layer, the filled layer having a similar composition to the visible side of the components described above. The problem with this layered construction is that the overall board is difficult to process since, in principle, different tools are required to machine or process the visible side (thin, filled layer), on the one hand, and the chipboard, on the other. In addition, chipboard has the disadvantage that it swells at higher levels of humidity and, in particular, during direct contact with water and so this type of board can be used, above all, in damp or humid rooms and particularly in kitchens as well only with reservations. The same applies for chipboard with a decorative, high-pressure laminated surface.